Comparison of Optical Coherence Tomography with Disc-Macula Distance to Disc Diameter Ratio in Diagnosing Optic Nerve Hypoplasia

Title Comparison of Optical Coherence Tomography with Disc-Macula Distance to Disc Diameter Ratio in Diagnosing Optic Nerve Hypoplasia
Author, Co-Author Yi Pang, Kelly Yin, Kelly Frantz
Topic Treatment and Management of Posterior Sgmt Disease
Year
2016
Day
Thursday
Program Number
165009
Room
Ballroom A-B
Affiliation
Illinois College of Optometry
Abstract

Purpose:  Optic nerve hypoplasia (ONH) is a developmental disorder characterized by a small optic disc and/or a reduced number of retinal nerve fibers. The purpose of the study was to evaluate whether Optical Coherence Tomography (OCT) is a valid test for diagnosing ONH compared to disc-macula distance to disc diameter (DM:DD) ratio. Furthermore, to determine the optimal cutoff value of OCT disc area to differentiate a hypoplastic disc from a normal optic disc.

Methods: A total of 29 subjects with ONH (6-66 years old) and 64 normal subjects (6-64 years old) were recruited and underwent comprehensive eye examinations, fundus photography and Cirrus spectral domain OCT. Only the left eye data of the control subjects were used for data analysis. Receiver operating characteristic curves (ROC) for DM:DD ratio and OCT disc area were constructed based on data from the ONH eyes and control eyes.

Results: Mean (± SD) OCT disc area was 1.89 (± 0.38) mm2 for the control eyes and 1.46 (± 0.42) mm2 for the ONH eyes (P < 0.0001). The area under the curve (AUC) for DM:DD ratio was 0.97 (95% confidence interval: 0.91-0.99). The AUC for OCT disc area was 0.79 (95% confidence interval: 0.70-0.86). A statistically significant difference was found between AUC for OCT disc area and that for DM:DD ratio (P = 0.0005). The optimal cutoff value for OCT disc area was 1.66 mm2 with 76% sensitivity and 70% specificity. The optimal cutoff value for DM:DD ratio was 3.10 with 85% sensitivity and 95% specificity.

Conclusions: We suggest the optimal cutoff value for OCT disc area as 1.66 mm2 in order to discriminate a hypoplastic disc from a normal optic disc. Both OCT and DM:DD ratio are valid tests to aid diagnosis of ONH. However, DM:DD ratio is superior to OCT in diagnosing ONH with higher sensitivity and specificity.

Affiliation of Co-Authors Illinois College of Optometry, Illinois College of Optometry
Outline